摘要
实验采用疏水性离子液体1-丁基-3-甲基咪唑六氟磷酸盐([C_4mim][PF_6])代替挥发性有机溶剂,由水相中萃取香豆素。采用紫外分光光度法测定了香豆素质量浓度,考察了温度、pH值、相比、香豆素质量浓度、萃取时间等因素对萃取效果的影响。结果表明,在10～50℃和pH=1～11条件下,温度和pH值对萃取效果几乎无影响;当萃取时间为10 min、V(香豆素水溶液):V([C_4mim][PF_6])=3:1、香豆素质量浓度为1.0g/L时,萃取效果最好;在该条件下,以100mL[C_4mim][PF_6]为萃取剂,平均萃取率达94.55%。离子液体中的香豆素用3倍体积量的NaOH水溶液反萃取3次,可将香豆素完全转移到水相;离子液体相用蒸馏水洗至中性,80℃减压干燥5 h后可重新使用。
Extraction of coumarin from aqueous solution was carried out using hydrophobic ionic liquid （IL）, 1 butyl-3-methylimidazolium hexafluorophosphate, to replace volatile organic solvents. UV spectrophotometry was employed to determine the mass concentration of coumarin. The effects of temperature, pH, phase ratio, the mass concentration of coumarin, and time on the extraction efficiency were investigated systematically. The results showed that the changes of temperature （from 10 ℃ to 50 ℃） and pH（from 1 to 11）had no obvious influence on the extraction efficiency; with the extraction time 10 min, V（coumarin aqueous solution） ： V（[C4mim][PF6]）=3 ： 1 and the mass con centration of coumarin 1.0 g/L, [C4mim][PF6]had its highest extraction efficiency. Under the optimal conditions, the average extraction rate of 4 times experiments was 94. 55% when 100 mL [C4mim][PF6] was used as extracting agent. The coumarin in the final I L phase was separated by back extraction with 3 times of volume of 1.0 mol/L NaOH aqueous solution. Usually, the coumarin could be transferred into water phase absolutely by three times of back extraction. The recovered IL was washed with distilled water to neutral, dried under reduced pressure at 80 ℃ for 5 h, and then could be reused for the next extraction.
出处
《精细石油化工》
CAS
CSCD
北大核心
2010年第2期28-32,共5页
Speciality Petrochemicals
基金
国家自然科学基金项目(20862001)
江西省自然科学基金项目(2009GQH0007
2008GZH0055
2008GQH0051)
江西省教育厅科技项目(GJJ10168
GJJ09259)
东华理工大学校长基金项目(DHXK0906)
